code: def suite():
      graph = unittest.defaultTestLoader.loadTestsFromTestCase(
          GraphTestRunner
      )
      clustering = unittest.defaultTestLoader.loadTestsFromTestCase(
          ClusteringTestRunner
      )
      return unittest.TestSuite([graph, clustering])
  
imports: import os
  import unittest
  from igraph import Graph, plot, VertexClustering, Layout
  from ...utils import overridden_configuration
label_desc: Use image node_id 1 for calling a global function with example usage: suite() and returns: unittest